The present invention relates generally to a method of feeding a calf and in particular the present invention relates to a method of feeding a calf an enhanced rate of an improved milk replacer containing an effective amount of carnitine.
The feeding of camitine to heifers, steers and lactating dairy cows is known in the art. PCT Application No. US95/02211, hereinafter the Blum et al application, discloses feeding ruminants such as heifers, steers and lactating dairy cows carnitine either orally or through tubes that discharge directly into the abomasum or rumen. The examples contained in the Blum et al application provided inconclusive or mixed results regarding the effectiveness of feeding heifers, steers and lactating dairy cows carnitine.
The Blum et al application discloses a number of trials including one that was conducted on the effectiveness of feeding carnitine to heifers at a rate of 0.6 grams per day and 1.2 grams per day in a feed consisting of 75 weight percent ground corn and 25 weight percent soybean meal while having access to hay. While average daily gain was statistically significantly greater for the heifers fed the carnitine as compared to the control at the midpoint of the experiment, at the end of the forty two day experiment there was no statistically significant difference in average daily weight gain in the heifers, whether the heifers were fed or were not fed carnitine. Additionally, no significant increase in average daily was recorded when the heifers were fed 1.2 grams of carnitine per day as compared to a rate of 0.6 grams of camitine per day.
Another experiment was conducted on the effectiveness of feeding camitine to ten month old steers. Again, the results were inconclusive as to the effectiveness of carnitine. When comparing individual backfat depths after a forty two day trial, the results indicated that steers fed 0.6 grams of camitine per day had the greatest increase in backfat depth, followed by the steers fed the control without carnitine. The least amount of backfat increase was found in the steers fed the most carnitine, 1.2 grams per day. The results were summarized as being inconclusive because of the high amount of variation in the measurements.
Another experiment provided results on the effect of feeding camitine to mature ruminally cannulated steers which were also mixed an inconclusive. The results indicated that camitine supplementation at high levels in a high roughage diet had little effect on nitrogen uptake from the rumen. Acetate to proprionate ratios were not effected by the supplementation of carnitine, although the acetate to proprionate ratios were effected by the time at which the samples were taken.
Additionally, results on the effect of feeding carnitine to lactating dairy cows, either dosed directly into the rumen or the abomasum, were also mixed and inconclusive. Milk production was not affected by dosing camitine into the rumen or abomasum. Additionally, milk fat content and milk fat yield were decreased when dosed directly into the abomasum. However, carnitine, whether dosed directly into the rumen or abomasum, tended to increase digestible and metabolized energy from the diet which was believed to be directed to body storage.
The Blum et al application speculates that feeding carnitine in a milk replacer would benefit young animals with underdeveloped rumens. However, the Blum et al application does not disclose feeding the milk replacer at enhanced feeding rates that provide higher dosages of carnitine.